Synthetic graphite material, synthetic graphite material production method, negative electrode for lithium ion secondary battery, and lithium ion secondary battery

Abstract

A synthetic graphite material wherein the crystal grain size L(112) in the c-axis direction as calculated from a (112) diffraction line obtained by wide-angle X-ray diffraction is 4-30 nm, the surface area based on volume as calculated by a laser diffraction-type particle size distribution measurement device is 0.22-1.70 m2 / cm3, the oil absorption is 67-147 mL / 100g, the spectra derived from carbon that appear in an electron spin resonance method measured by using the X band is within the range 3200-3410 gauss, and [delta]Hpp, which is the spectral line width calculated from the first derivative spectra for said spectra at the temperature of 4.8 K, is 41-69 gauss.

Description

technical field

[0001] The invention relates to an artificial graphite material, a manufacturing method of the artificial graphite material, a negative electrode for a lithium-ion secondary battery, and a lithium-ion secondary battery.

[0002] This application claims priority based on Japanese Patent Application No. 2019-004664 for which it applied in Japan on January 15, 2019, and uses the content here. Background technique

[0003] Lithium-ion secondary batteries are used in industrial applications such as automobiles and power storage for system infrastructure.

[0004] Graphite, such as an artificial graphite material, is used as a negative electrode material of a lithium ion secondary battery (for example, refer patent document 1.).

[0005] Batteries suitable for automotive use are used in a wide temperature range from low temperatures below 0°C to high temperatures above 60°C. However, in a lithium ion secondary battery using graphite as a negative electrode materi...

Examples

Embodiment 1

[0188] For desulfurized vacuum light oil (sulfur content 500 mass ppm, density at 15°C 0.88g / cm 3 ) was subjected to fluid catalytic cracking to obtain a fluid catalytic cracking residue (hereinafter referred to as "fluid catalytic cracking residue (A)"). The obtained fluid catalytic cracking residue (A) had an initial boiling point of 220°C, a sulfur content of 0.2% by mass, and an aromatic content of 60% by mass. In addition, hydrodesulfurization was performed on an atmospheric distillation residue with a sulfur content of 3.5% by mass in the presence of a Ni-Mo catalyst so that the hydrolysis rate became 30% or less, and a hydrodesulfurized oil (hereinafter referred to as as "hydrodesulfurized oil (A)".). The obtained hydrodesulfurized oil (A) had an initial boiling point of 260°C, a sulfur content of 0.3% by mass, an asphaltene content of 1% by mass, a saturated content of 70% by mass, and a density of 0.92 g / cm at 15°C. 3 .

[0189] Next, desulfurized vacuum light oil ...

Embodiment 2

[0203]The feed oil composition was obtained by mixing desulfurized fluid catalytic cracking residue (B-1), fluid catalytic cracking residue (A) and hydrodesulfurized oil (A) at a mass ratio of 15:65:20. This raw material oil composition was put into a test tube, and heat-treated at normal pressure and 500 degreeC for 3 hours, and coking was performed, and the raw material coke composition was obtained. This raw coke composition was pulverized by a hammer mill so that the average particle diameter measured by a laser diffraction particle size distribution analyzer was 18.8 μm. The obtained pulverized product was fired at 1000° C. under a nitrogen gas flow to obtain calcined coke. At this time, the heating time from room temperature to 1000°C is set to 4 hours, the holding time at 1000°C is set to 4 hours, and the cooling time from 1000°C to 410°C is set to 2 hours. Let cool on the air side for 4 hours. The obtained calcined coke was put into a graphite crucible, and graphitiz...

Embodiment 3

[0205] The feedstock oil composition was obtained by mixing desulfurized fluid catalytic cracking residue (B-1), fluid catalytic cracking residue (A) and hydrodesulfurized oil (A) at a mass ratio of 40:40:20. This raw material oil composition was put into a test tube, and heat-treated at normal pressure and 500 degreeC for 3 hours, and coking was performed, and the raw material coke composition was obtained. This raw coke composition was pulverized with a hammer mill so that the average particle diameter measured by a laser diffraction particle size distribution analyzer became 20.5 μm. The obtained pulverized product was fired at 1000° C. under a nitrogen gas flow to obtain calcined coke. At this time, the heating time from room temperature to 1000°C is set to 4 hours, the holding time at 1000°C is set to 4 hours, and the cooling time from 1000°C to 410°C is set to 2 hours. Let cool on the air side for 4 hours. The obtained calcined coke was put into a graphite crucible, an...

technical field

[0001] The invention relates to an artificial graphite material, a manufacturing method of the artificial graphite material, a negative electrode for a lithium-ion secondary battery, and a lithium-ion secondary battery.

[0002] This application claims priority based on Japanese Patent Application No. 2019-004664 for which it applied in Japan on January 15, 2019, and uses the content here. Background technique

[0003] Lithium-ion secondary batteries are used in industrial applications such as automobiles and power storage for system infrastructure.

[0004] Graphite, such as an artificial graphite material, is used as a negative electrode material of a lithium ion secondary battery (for example, refer patent document 1.).

[0005] Batteries suitable for automotive use are used in a wide temperature range from low temperatures below 0°C to high temperatures above 60°C. However, in a lithium ion secondary battery using graphite as a negative electrode materi...

Examples

Embodiment 1

[0188] For desulfurized vacuum light oil (sulfur content 500 mass ppm, density at 15°C 0.88g / cm 3 ) was subjected to fluid catalytic cracking to obtain a fluid catalytic cracking residue (hereinafter referred to as "fluid catalytic cracking residue (A)"). The obtained fluid catalytic cracking residue (A) had an initial boiling point of 220°C, a sulfur content of 0.2% by mass, and an aromatic content of 60% by mass. In addition, hydrodesulfurization was performed on an atmospheric distillation residue with a sulfur content of 3.5% by mass in the presence of a Ni-Mo catalyst so that the hydrolysis rate became 30% or less, and a hydrodesulfurized oil (hereinafter referred to as as "hydrodesulfurized oil (A)".). The obtained hydrodesulfurized oil (A) had an initial boiling point of 260°C, a sulfur content of 0.3% by mass, an asphaltene content of 1% by mass, a saturated content of 70% by mass, and a density of 0.92 g / cm at 15°C. 3 .

[0189] Next, desulfurized vacuum light oil ...

Embodiment 2

[0203]The feed oil composition was obtained by mixing desulfurized fluid catalytic cracking residue (B-1), fluid catalytic cracking residue (A) and hydrodesulfurized oil (A) at a mass ratio of 15:65:20. This raw material oil composition was put into a test tube, and heat-treated at normal pressure and 500 degreeC for 3 hours, and coking was performed, and the raw material coke composition was obtained. This raw coke composition was pulverized by a hammer mill so that the average particle diameter measured by a laser diffraction particle size distribution analyzer was 18.8 μm. The obtained pulverized product was fired at 1000° C. under a nitrogen gas flow to obtain calcined coke. At this time, the heating time from room temperature to 1000°C is set to 4 hours, the holding time at 1000°C is set to 4 hours, and the cooling time from 1000°C to 410°C is set to 2 hours. Let cool on the air side for 4 hours. The obtained calcined coke was put into a graphite crucible, and graphitiz...

Embodiment 3

[0205] The feedstock oil composition was obtained by mixing desulfurized fluid catalytic cracking residue (B-1), fluid catalytic cracking residue (A) and hydrodesulfurized oil (A) at a mass ratio of 40:40:20. This raw material oil composition was put into a test tube, and heat-treated at normal pressure and 500 degreeC for 3 hours, and coking was performed, and the raw material coke composition was obtained. This raw coke composition was pulverized with a hammer mill so that the average particle diameter measured by a laser diffraction particle size distribution analyzer became 20.5 μm. The obtained pulverized product was fired at 1000° C. under a nitrogen gas flow to obtain calcined coke. At this time, the heating time from room temperature to 1000°C is set to 4 hours, the holding time at 1000°C is set to 4 hours, and the cooling time from 1000°C to 410°C is set to 2 hours. Let cool on the air side for 4 hours. The obtained calcined coke was put into a graphite crucible, an...

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